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Tournament Of Towns
1989 Tournament Of Towns
(239) 3
(239) 3
Part of
1989 Tournament Of Towns
Problems
(1)
TOT 239 1989 Autumn A S3 area of cross wanted, rotate _|_lines, circle
Source:
3/12/2021
Choose a point
A
A
A
inside a circle of radius
R
R
R
. Construct a pair of perpendicular lines through
A
A
A
. Then rotate these lines through the same angle
V
V
V
about
A
A
A
. The figure formed inside the circle, as the lines move from their initial to their final position, is in the form of a cross with its centre at
A
A
A
. Find the area of this cross.(Problem from Latvia)
geometry
area